Dear Groamcs user, <br> <br>I'm trying to do something about peptides aggregation, but the timescale is unendurable.
<br>A paper has ever refered that by the using of position constraint can greatly reduce the <br>timescale for the appearance of anti-parallel beta-sheet conformation of peptides. <br>Now,i want to constraint the positions of the peptides by
<br>harmonic coupling [the spring constant, kc, is 0.03 kcal/(mol A° )] <br>between the center of the water box and the oligomer center of mass. <br>
<br>Does anyone know how to add this constraint? <br> <br>Thanks!
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